package com.subside.test;

import java.util.HashMap;

/**
 * @Author : zhangbo
 * @data : 2024/5/14
 * @description :
 */
public class test2 {
    public static void main(String[] args) {
        HashMap<String,String>map =new HashMap<>();
        map.put("1","张三");
        //return oldValue
        System.out.println(map.put("1", "李四"));
    }
}
